Filling composition for brake shoes



' proportions of both asbestos and coke, and.

Patented Sept. 19, 1922.

GUY L. MoIN'TYRE, OF PITTSBURGH, BENNSYLVANIA.

FILLING COMPOSITION FOR BRAKE SHOES.

' No Drawing.

To all w 1mm, it nut-y concern:

Be it known that I, GUY L. MCINTYRE, a citizen of the United States, and resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in a Filling Composition for Brake Shoes, of which the following is a specification.

This invention relates to a filling composition for brake shoes.

Composition brake shoes for steam and street railway rolling stock are manufactured by'mixing a composition of certain prepared substances and pressin such composition into a suitable brake Shoe casing. Such compositions in general comprise a friction producin metal in a finely divided condition; a bin mg substance, which may be oxidizable or drying oil, such as linseed oil and suitable filling substances for preventing burning of the brake shoes and to moderate the friction produced by the metal in the composition.

The object of the present invention is to provide an economical composition from which brake shoes of increased wearing qualities may be produced.

This object is effected by the provision of substances, or greater relative proportions of substances which impart a longer life to the brake shoes, and by the elimination of certain hitherto used but less desirable substances.

More specifically the composition of the present invention comprises relatively high dispenses with the use of other substances such as plumbago, plaster, and sal ammoniac. The proportion of friction increasing metal which is included is also relatively low in comparison with the proportion of coke included.

A further object of the invention is to provide a filling composition for brake shoes, in which the friction of the brake shoe may be adjusted by varying the relative proportions of the ingredients without the inclusion of any additional substance or substances.

The friction increasing metal employed may desirably be cast iron in the form of relatively fine borings, filings, or the like; while linseed oil, or china wood oil, forms a suitable binder for the entire composition. The asbestos employed should be in a generally shredded or fibrous state, and the coke Application filed August 2, 1820. Serial No. 400,817.

Iron 24 parts.

Linseed oil 7 parts. Asbestos 28 parts. (Joke 32 parts.

It will be seen from the formula. given above that the asbestos provides approximately 30% of the weight of the composition, while the coke provides approximately 35% by weigh of the composition. Together they form approximately 65% of the total composition. It is desirable that the combined asbestos and coke should exceed sixty per cent of the total composition; the percentage of friction increasing metal being thus less than forty per cent of the total composition in any variation of the relative proportions of the component substances.

It is to be understood that the essence of the present invention resides in the inclusion of the relatively high proportion of asbestos and coke. hen desirable, the proportion of these substances may be further increased and the proportion of the friction producing metal decreased, or even eliminated, without the necessity for including any additional substance or substances.

The asbestos in addition to its function of preventing burning of the brake shoe, also has a tendency to increase the friction. Coke in increased quantities has a tendency to lessen the friction. The relative proportions of these substances to each other, as Well as to the friction increasing metal, may therefore be varied to increase or decrease the friction of the brake shoe.

The scope of the invention is not, therefore, restricted to the exact proportions given, but is restricted only by the limitations contained in the claims appended thereto.

What I claim is:

1. Av filling composition for brake shoes comprising a friction increasing metal and a viscous binding material; and asbestos and coke in a combined proportion exceeding 110 s1xty per cent by weight of the total com-- position.

2. A filliiig composition for brake shoes ty-oneparts by weight, asbestos twenty eight parts, coke thirty-two parts, ironfi twenty-four parts, and a drying oil seven parts. I

' 5. A filling'composition for brake shoes comprising a friction producing metal, a drying 011, and asbestos and coke in a com-' bined proportion exceeding sixty per cent by weight of the total composition.

6. A filling composition for brake shoes comprising a friction increasing metal and a viscous binding material, coke, and asbestos in excess of thirty per cent by weight of the total composition.

7 In a filling composition for brake shoes,

' coke and asbestos in a combined proportion exceeding sixty per cent by Weight of the total composition.

8. A frictional composition composed of fibre, coke, iron and a binder oil. y

9. A frictional composition composed of a fibrous material, a non expanding absorbent material, a resistant material and a binder.

10. A frictional composition composed of fibrous material,-a non expanding heat absorbent material, a resistant material, and a binder. i

1.1; A frictional composition composed of a fibrous material, a non expanding fluid absorbent-material, a resistant material, and a fluid binder.

12. A frictional composition composed of I asbestos'fibre, ground coke, iron borings, and linseed oil.

13. A frictional composition, the solid constituents of which are fibre, coke and iron.

posed of fibre, coke and resistant borings.

frictional composition of which at. least seventy-five per cent by weight is com- 15. A frictional composition of which'substantially ninety per cent by weight is conr posed of fibre, coke and resistant borings.

16. A frictional composition comprising fibre, coke, and resistant borings in proportions which differ but slightly by weight.

17. A frictional composition the solid constituents of which are fibre,'a non-expanding absorbentmaterial, and a resistant material.

18. A frictional composition the solid constituents of which are fibre, a non-expanding absorbent material, and iron.

19. A frictional composition having coke as a large constituent.

20. A frictional composition having coke as the largest constituent by Weight.

In witness whereof, I hereunto set my hand.

GUY L. MOINTYREE.

lVitnesses:

C. L. BU'I'IERFIELD, GRETTA W. ALs'roN. 

